CRF (human, rat) Acetate

Corticotropin-releasing hormone (CRH), a peptide hormone that stimulates both the synthesis and the secretion of adrenocorticotropic hormone (ACTH) in the corticotropin-producing cells (corticotrophs) of the anterior pituitary gland. CRH consists of a single chain of 41 amino acids. Many factors of neuronal and hormonal origin regulate the secretion of CRH, and it is the final common element that directs the body’s response to many forms of stress, including physical and emotional stresses and external and internal stresses.

A 37-kDa corticotropin releasing factor (CRF) binding protein (CRF-BP) was purified from human plasma by repeated affinity purification and subsequently sequenced and cloned. The human and rat CRF-BP cDNAs encode proteins of 322 amino acids with one putative signal sequence, one N-glycosylation site, and 10 conserved cysteines. Human CRF-BP binds human CRF with high affinity but has low affinity for the ovine peptide. In contrast, sheep CRF-BP binds human and ovine CRF with high affinity. The CRF-BP gene consists of seven exons and six introns and is located on chromosome 13 and loci 5q of the mouse and human genomes, respectively. CRF-BP inhibits the adrenocorticotrophic hormone (ACTH) releasing properties of CRF in vitro. CRF-BP dimerizes after binding CRF and clears the peptide from blood. This clearance mechanism protects the maternal pituitary gland from elevated plasma CRF levels found during the third trimester of human pregnancy.

Behan, D. P., De Souza, E. B., Lowry, P. J., Potter, E., Sawchenko, P., & Vale, W. W. (1995). Corticotropin releasing factor (CRF) binding protein: a novel regulator of CRF and related peptides. Frontiers in neuroendocrinology, 16(4), 362-382.

Corticotropin-releasing factor (CRF) is localized in fibers in the noradrenergic nucleus locus ceruleus (LC) and alters LC discharge characteristics when administered centrally. To determine whether CRF functions as a neurotransmitter in the LC during stress, the effects of hemodynamic stress on LC discharge were compared to those of CRF. Hemodynamic stress elicited by intravenous nitroprusside infusion produced identical effects on LC spontaneous and sensory-evoked discharge as those reported for centrally administered CRF. Thus, nitroprusside increased LC spontaneous discharge rates, and disrupted LC discharge evoked by sensory stimuli such that the stimuli were less effective in producing phasic increases in LC discharge.

Valentino, R. J., & Wehby, R. G. (1988). Corticotropin-releasing factor: evidence for a neurotransmitter role in the locus ceruleus during hemodynamic stress. Neuroendocrinology, 48(6), 674-677.